The overall objective of this protocol is to coordinate and integrate the investigative activities of four New England pediatric oncology centers (Brown University/Rhode Island Hospital, Dartmouth College/Dartmouth-Hitchcock Medical Center - Norris Cotton Cancer Center, Harvard University/Massachusetts General Hospital, University of Vermont/Medical Center Hospital - Vermont Regional Cancer Center) into a single program, the New England Pediatric Oncology Consortium (NEPOC), which, through active membership in the Southwest Oncology Group (SWOG), will effectively contribute to the development of a greater understanding of and more effective treatments for malignancies in children. Through formalization and efficient organization of cooperative efforts, the most effective use of the resources of each institution will be achieved and enable full participation and significant input into the activities of SWOG.